.justify-content-center {
    display: flex;
    justify-content: center;
}

.justify-content-between {
    display: flex;
    justify-content: space-between;
}

.justify-content-around {
    display: flex;
    justify-content: space-around;
}

.justify-content-start {
    display: flex;
    justify-content: flex-start;
}

.flex-wrap-wrap {
    display: flex;
    flex-wrap: wrap;
}

.flex-wrap-nowrap {
    display: flex;
    flex-wrap: nowrap;
}

.align-items-center {
    display: flex;
    align-items: center;
}

.align-items-end {
    display: flex;
    align-items: flex-end;
}

.flex-direction-column-reverse {
    display: flex;
    flex-direction: column-reverse;
}

.font-size-20 {
    font-size: 20px;
}

.font-size-50 {
    font-size: 50px;
}

.font-red-size-30 {
    color: yellow;
    font-size: 30px;
}

.text-align-center {
    text-align: center;
}

/*单行溢出*/
.single-over {
    /*超过隐藏*/
    overflow: hidden;
    /*不换行*/
    white-space: nowrap;
    /*以...表示*/
    text-overflow: ellipsis;
}

/*多行溢出*/
.many-over {
    display: -webkit-box;
    -webkit-box-orient: vertical;
    text-overflow: ellipsis;
    -webkit-line-clamp: 3;
    overflow: hidden;
}

.border {
    border: 1px solid red;
}

.border-gray {
    border: 1px solid gray;
}

* {
    margin: 0;
}

.title-bar {
    color: rgb(230, 145, 55);
    font-size: 20px;
    padding: 10px;
}

.border-top {
    border-top: 1px solid gray;
    padding: 10px;
}

.font-title {
    color: black;
    font-size: 20px;
    cursor: pointer;
}

.font-title:hover {
    color: blue;
    text-decoration: underline;
}

.font-content {
    color: gray;
    font-size: 10px;
}

.width-1000 {
    width: 1000px;
}

.width-900 {
    width: 900px;
}

/*----------------------中间内容-------------*/
.middle {
    margin: 30px 0;
}
